if you are just looking to replace the bulb then you don't have to take the headlamp assembly out. you may have to remove the battery to get to it depending on what side the battery is on. if the air filter is in the way, you can usually remove the snorkel by pulling up on it or just remove the filter housing bolts to move it out of the way.
there is a connector that you can reach behnd the headlamp from inside the engine compartment. just turn that connector counter-clockwise (to the left) to release the clips and pull it out. the bulb will come out with the socket. then press down on the bulb and turn it in the socket to remove the bulb.
the bolt you refer to is for the headlamp assembly that includes the lens. the only way to get the headlamp housing out is to remove the bumper and you don't need to do that to change a turn signal bulb.
hope that helps